The present invention relates to burner devices, and, more particularly, to burner assemblies, modules and adapters for producing an inorganic soot.
It is known to form various articles, such as crucibles, tubing, lenses, and optical waveguides, by reacting a precursor in the flame of a burner to produce a soot and then depositing the soot on a receptor surface. This process is particularly useful for the formation of optical waveguide preforms made from doped and undoped silica soot, including planar waveguides and waveguide fibers.
The waveguide formation process generally involves reacting a silicon-containing precursor in a burner flame generated by a combustible gas, such as a mixture of methane and oxygen, and depositing the silica soot on an appropriately shaped receptor surface. In this process, silicon-containing materials typically are vaporized at a location remote from the burner. The vaporized raw materials are transported to the burner by a carrier gas. There, they are volatilized and hydrolyzed to produce soot particles. The soot particles then collect on the receptor surface. The receptor surface may be a flat substrate in the case of planar waveguide fabrication, a rotating starting rod (bait tube) in the case of vapor axial deposition (VAD) for waveguide fiber fabrication, or a rotating mandrel in the case of outside vapor deposition (OVD) for waveguide fiber fabrication.
Numerous burner designs have been developed for use in vapor delivery precursor processes, and at least one liquid delivery precursor process has been contemplated. Whether the precursor is delivered to the burner in vapor form or liquid form, it is important that the burner receives a distributed, even stream of precursor. This consideration is particularly important during waveguide manufacture to form accurate refractive index profiles.
According to embodiments of the present invention, a burner module for delivering a flow of chemical reactants to a combustion site of a chemical vapor deposition process includes a plurality of substantially planar layers. The burner modules are generally rectangular is shape such that they may be arranged in side-by-side orientation. The substantially planar layers of the burner module are arranged in a generally parallel and fixed relationship and define an inlet, an outlet and a passage fluidly connecting the inlet and the outlet. At least one of the layers is a distribution layer having a plurality of apertures therethrough and fluidly communicating with the passage. The plurality of apertures collectively define a non-uniform pattern arranged and configured to improve the uniformity of a flow out through the outlet.
According to further embodiments of the present invention, a burner mounting adapter for use with a manifold having a mount surface and first and second fluid supply openings in the mount surface and distributed at different locations along a length of the manifold includes an adapter body. A first inlet aperture, a first outlet aperture and a first connecting passage fluidly connecting the first inlet and outlet apertures are defined in the adapter body. A second inlet aperture, a second outlet aperture and a second connecting passage fluidly connecting the second inlet and outlet apertures are defined in the adapter body. The first and second inlet apertures are arranged and configured to align with the first and second fluid supply openings, respectively, when the burner mounting adapter is mounted on the mount surface of the manifold. The first and second passages extend transversely of the manifold length when the burner mounting adapter is mounted on the mount surface of the manifold. Thus, it should be recognized that the burner mounting adapter connects the macro scale of the manifold to the micro scale of the burner face.
According to further embodiments of the present invention, a burner module for use with a manifold having a mount surface and first and second fluid supply openings in the mount surface and distributed at different locations along a length of the manifold includes a burner mounting adapter. The burner mounting adapter includes an adapter body. A first inlet aperture, a first outlet aperture and a first connecting passage fluidly connecting the first inlet and outlet apertures are defined in the adapter body. A second inlet aperture, a second outlet aperture and a second connecting passage fluidly connecting the second inlet and outlet apertures are defined in the adapter body. The first and second inlet apertures are arranged and configured to align with the first and second fluid supply openings, respectively, when the burner mounting adapter is mounted on the mount surface of the manifold. The first and second passages extend transversely of the manifold length when the burner mounting adapter is mounted on the mount surface of the manifold. A burner face layer overlies the adapter body and the distribution layers. The burner face layer includes at least first and second burner apertures fluidly communicating with the first and second outlet apertures of the adapter body, respectively.
According to further embodiments of the present invention, a burner assembly for delivering a flow of chemical reactants to a combustion site of a chemical vapor deposition process includes a manifold and a burner module. The manifold includes a mount surface with first and second fluid supply openings distributed at different locations along a length of the manifold. The burner module includes a burner mounting adapter including an adapter body. A first inlet aperture, a first outlet aperture and a first connecting passage fluidly connecting the first inlet and outlet apertures are defined in the adapter body. A second inlet aperture, a second outlet aperture and a second connecting passage fluidly connecting the second inlet and outlet apertures are defined in the adapter body. The first and second inlet apertures are arranged and configured to align with the first and second fluid supply openings, respectively, when the burner mounting adapter is mounted on the mount surface of the manifold. The first and second passages extend transversely of the manifold length when the burner mounting adapter is mounted on the mount surface of the manifold. A burner face layer overlies the adapter body. The burner face layer includes at least first and second burner apertures fluidly communicating with the first and second outlet apertures of the adapter body, respectively.
According to further embodiments of the present invention, a burner module for delivering a flow of chemical reactants to a combustion site of a chemical vapor deposition process includes a burner face layer and a reflective layer covering the burner face layer.
Further features, advantages and details of the present invention will be appreciated by those of ordinary skill in the art from a reading of the Figs. and the detailed description of the preferred embodiments which follow, such description being merely illustrative of the present invention.